Add integration test harness with dedicated test Stellar network

[Smartdevs17]

Context

Integration tests currently run against a shared Stellar testnet, causing flaky tests due to sequence number conflicts, account limits, and rate limiting.

Current Limitation/Problem

Shared testnet accounts cause test interference. Rate limits cause random test failures. State leaks between test suites.

Expected Outcome

Dedicated test Stellar network: Dockerized Soroban standalone for contract integration tests, ephemeral per-test accounts, automatic cleanup, and snapshot/restore for speed.

Acceptance Criteria

• Dockerized Stellar standalone: pre-configured Docker image for CI and local use
• Per-test accounts: fresh Stellar account funded with friendbot per test case, destroyed after
• Test lifecycle hooks: beforeAll (deploy contracts, fund accounts), afterAll (cleanup all accounts)
• Snapshot/restore: snapshot container state after contract deployment, restore per test suite
• CI integration: GitHub Actions service container with Soroban standalone image
• Failsafe: 30s timeout per test, automatic retry on sequence number error (max 2 retries)
• Performance: full contract test suite completes in <2 minutes (vs 10+ min on shared testnet)
• Edge case: snapshot corruption recovery (re-deploy contracts from clean state)

Technical Scope

• docker/stellar-standalone.Dockerfile - test Stellar network Docker image
• docker-compose.test.yml - test environment composition
• scripts/test-integration.sh - integration test runner
• packages/test-harness/ - test fixture utilities (deployContract, fundAccount, invokeContract)
• .github/workflows/integration-tests.yml - CI integration test workflow
• contracts/test-helpers/ - deploy, fund, invoke helper functions

[Michael997glitch]

@Michael997glitch has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

I’ve resolved similar problems in the past and am confident I can implement a clean, efficient fix quickly,if am given the opportunity.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Michael997glitch to this issue.

[Menjay7]

@Menjay7 has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi! I came across this issue and would love to work on it. I have experience with similar tasks and I'm confident I can investigate, implement a clean solution, and thoroughly test it before submitting a PR. If the issue is still open, I would appreciate it if you could assign it to me.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Menjay7 to this issue.

[drips-wave]

Congratulations, @Michael997glitch! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 30, 2026.

🧑‍💻 @Michael997glitch: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

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